Shooting a firearm with precision accuracy, particularly during combat, requires a steady and stable rifle support. Stabilizing the rifle manually, relying solely on body support, is difficult for the degree of stability needed for long range or small target accuracy. Therefore, mechanical support devices are used as a means for stabilizing the weapon and improving accuracy.
Stabilizing devices include various slings, shooting sticks, bipods and tripods. In recent times, compact collapsible and/or extendable bipods have been developed. Collapsible bipods are relatively lightweight and are mountable to the forearm stock or mounting rail of a firearm. These bipods include a pair of legs that can be pivoted from a tucked position adjacent the firearm stock to a down position to support the barrel on a support surface. Extendable bipods allow the length of the legs to be extended.
Tracking a moving target typically requires several different motions of the firearm. One motion is a horizontal or lateral rotation, also referred to as “panning.” Another motion is the vertical rotation of the firearm, also referred to as “tilting.” A third motion is sometimes required if the bipod legs are on an uneven support surface, requiring the firearm to be rotated on the support axis in order to stay vertically aligned with the gravity force. This motion is referred to as “canting.”
Bipods have been made that are retractable within a housing that also serves as a forward handgrip. For example, U.S. Pat. No. 7,111,424 (Moody et al) discloses a fore end handgrip in the form of a tubular housing that holds a concealable bipod. The bipod legs deploy from the handgrip and lock in the extended position when a latch releases a spring. However, the locked bipod then restricts the above-mentioned motions (panning, tilting, and canting).
U.S. Pat. Publication No. 2005/0241206 (Teetzel et al.) discloses a similar hollow fore end grip with a retractable bipod. The bipod grip allows horizontal planning, and provides stop members to limit the degree of horizontal panning of the weapon relative to the bipod leg. The relative rotation permits the weapon to be horizontally pivoted to engage the target without the need to move or shift the bipod feet relative to the underlying support surface, but when the weapon is lifted there is no restoring force to return the bipod legs to alignment with the bore of the weapon.
Sometimes it is required to pan along the path of a moving target. If the target stops and allows time to obtain a good sight picture, it would be an advantage to be able to lift the weapon to take the weight off of the bipod legs and have the legs automatically return to alignment with the bore while achieving a precise sight picture prior to making the shot. It would be advantageous, therefore, to have a quick-deployment bipod that tracks the horizontal rotation angle of the firearm and enables a quick realignment of the bipod.
It would also be an advantage to have a release mechanism for the bipod release that is reliable and difficult to jam with dirt or debris.